In addition to conferring shape and rigidity to the aircraft fuselage, load frames are structural elements in charge of withstanding and transferring the loads from other structural elements of the aircraft, such as the wings or stabilizers.
In the state of the art, the manufacture of the frames is carried out by using machined metal structures or shaped sheet metal structures in which that part that withstands most of the load is reinforced with machined parts. In the case of shaped sheet metal. The section that is normally used is obtained in two pieces; on one hand the Z is manufactured, and on the other hand, the brackets which are riveted to the former section are manufactured.
This process has the drawback that long assembly times are necessary and that the final weight is much greater than what would be desired.